Because it is relatively inexpensive, carbon steel is the workhorse of the petrochemical industry. Chromium alloying is known to improve the corrosion resistance of carbon steel, but chromium is an expensive element. Thus, approaches whereby corrosion resistance can be achieved without expensive alloying are desirable.
Pearlite is a microstructural constituent of steels which is made up of alternating layers of ferrite (body centered cubic iron) and cementite (Fe3C). The pearlite microstructure is particularly resistant to certain forms of acid corrosion such as, for example, corrosion by organic acids. Thus, pearlite could be a ready substitute for expensive chromium alloying, however, the strength characteristics of pearlite limit its use as a bulk structural material for many applications since pearlite is produced from carbon steels containing at least 0.77% carbon.
Thus, what is needed in the art is a process for producing pearlite from an iron containing article which process preserves the mechanical properties of the article.